Pest description and damage These closely related beetles are about 0.125 inch long, brown, and oval. They feed on a wide variety of stored products: cereals, seeds, spices, tobacco, dried fruits and nuts, dried skins, feathers, and preserved animal products.
Locate and destroy the source of infestation. Place infested materials in the freezer for three or four days to kill pests, then discard. Thoroughly clean shelves and storage areas. Attachments for some types of vacuum cleaners are useful in removing food particles that may have become lodged in cracks. Clean surfaces with soap and water. Where freezing and vacuuming are not appropriate or adequate, treatment by a qualified professional may be required.
For further information:
How to Manage Pests/Pests in Gardens and Landscapes/Boxelder Bug. University of California. http://ipm.ucanr.edu/PMG/PESTNOTES/pn74114.html